The Cryogenics and Xenon handling system for the PandaX-4T Experiment

TL;DR

This paper reports on the design, commissioning, and performance of the cryogenics and xenon handling system for the PandaX-4T dark matter detector, achieving high cooling power, efficient purification, and effective xenon circulation.

Contribution

It introduces a large-scale cryogenics and xenon handling system with optimized cooling, purification, and circulation capabilities for the PandaX-4T detector.

Findings

Maximum cooling power of ~580 W at 178 K achieved

Filling rate of ~700 kg/day with nitrogen cooling

Purification speed of ~155 slpm with high heat exchange efficiency

Abstract

PandaX-4T, the new generation of the PandaX detector, is a xenon dual-phase detector with about six tons of liquid xenon as target for dark matter search. A cryogenics and xenon handling system is designed to liquify and purify this large detector. In this paper, the results on the commission of the cryogenics and gas handling system are reported. The maximum cooling power of ~ 580 W at 178 K with three cooperating coldheads has been achieved. The filling rate with an assisted liquid nitrogen cooling can reach ~ 700 kg/day. The average rate of recuperation by liquid nitrogen is around 440 kg/day. The maximum total purification speed of two circulation loops is up to ~ 155 slpm. Each loop is using a large heat exchanger with a measured heat exchange efficiency of ~ 97.5+-0.5%.